Many liquid or viscous products, such as glues, hand lotions, shampoos, food products such as ketchup, mustard and sauces are bottled in plastic containers or bottles. Plastic provides a lightweight inexpensive method of marketing a product.
To extract product from conventional containers, the user generally turns the bottle over allowing the force of gravity to draw the liquid out the opening. To enhance the pourability of some bottles, the front and rear surfaces of the bottle are made thinner or more flexible than the sides or edges of the bottle, permitting the bottle to be squeezed, urging the contents out. The squeezability of the bottle is normally a key marketing feature. However, many small children and elderly persons find squeezing a regular squeezable bottle difficult. Some children have a tendency to over-squeeze the bottle spilling the contents of bottle.
In order to overcome this problem, producers of liquid or viscous products have used pumps mounted in the mouth of the bottle. Many types of pump nozzles are well known in the art, including the pumps disclosed in the following U.S. Pat. Nos.: 4,120,429, 4,120,430, 4,352,443, 4,606,477, 4,863,070. However, the cost of such pumps detract from the potential marketing gain.